From: "Matthew Wilcox (Oracle)" willy@infradead.org
stable inclusion from stable-v6.6.35 commit 8394dce135733329c143097351e1893ade6a69cd category: bugfix bugzilla: https://gitee.com/src-openeuler/kernel/issues/IA8AIS CVE: CVE-2024-39469
Reference: https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?i...
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[ Upstream commit 09a46acb3697e50548bb265afa1d79163659dd85 ]
In prepartion for switching from kmap() to kmap_local(), return the kmap address from nilfs_get_page() instead of having the caller look up page_address().
[konishi.ryusuke: fixed a missing blank line after declaration] Link: https://lkml.kernel.org/r/20231127143036.2425-7-konishi.ryusuke@gmail.com Signed-off-by: Matthew Wilcox (Oracle) willy@infradead.org Signed-off-by: Ryusuke Konishi konishi.ryusuke@gmail.com Signed-off-by: Andrew Morton akpm@linux-foundation.org Stable-dep-of: 7373a51e7998 ("nilfs2: fix nilfs_empty_dir() misjudgment and long loop on I/O errors") Signed-off-by: Sasha Levin sashal@kernel.org Signed-off-by: Yu Liao liaoyu15@huawei.com --- fs/nilfs2/dir.c | 57 +++++++++++++++++++++++-------------------------- 1 file changed, 27 insertions(+), 30 deletions(-)
diff --git a/fs/nilfs2/dir.c b/fs/nilfs2/dir.c index 929edc0b101a..c6b88be8a9d7 100644 --- a/fs/nilfs2/dir.c +++ b/fs/nilfs2/dir.c @@ -186,19 +186,24 @@ static bool nilfs_check_page(struct page *page) return false; }
-static struct page *nilfs_get_page(struct inode *dir, unsigned long n) +static void *nilfs_get_page(struct inode *dir, unsigned long n, + struct page **pagep) { struct address_space *mapping = dir->i_mapping; struct page *page = read_mapping_page(mapping, n, NULL); + void *kaddr;
- if (!IS_ERR(page)) { - kmap(page); - if (unlikely(!PageChecked(page))) { - if (!nilfs_check_page(page)) - goto fail; - } + if (IS_ERR(page)) + return page; + + kaddr = kmap(page); + if (unlikely(!PageChecked(page))) { + if (!nilfs_check_page(page)) + goto fail; } - return page; + + *pagep = page; + return kaddr;
fail: nilfs_put_page(page); @@ -275,14 +280,14 @@ static int nilfs_readdir(struct file *file, struct dir_context *ctx) for ( ; n < npages; n++, offset = 0) { char *kaddr, *limit; struct nilfs_dir_entry *de; - struct page *page = nilfs_get_page(inode, n); + struct page *page;
- if (IS_ERR(page)) { + kaddr = nilfs_get_page(inode, n, &page); + if (IS_ERR(kaddr)) { nilfs_error(sb, "bad page in #%lu", inode->i_ino); ctx->pos += PAGE_SIZE - offset; return -EIO; } - kaddr = page_address(page); de = (struct nilfs_dir_entry *)(kaddr + offset); limit = kaddr + nilfs_last_byte(inode, n) - NILFS_DIR_REC_LEN(1); @@ -345,11 +350,9 @@ nilfs_find_entry(struct inode *dir, const struct qstr *qstr, start = 0; n = start; do { - char *kaddr; + char *kaddr = nilfs_get_page(dir, n, &page);
- page = nilfs_get_page(dir, n); - if (!IS_ERR(page)) { - kaddr = page_address(page); + if (!IS_ERR(kaddr)) { de = (struct nilfs_dir_entry *)kaddr; kaddr += nilfs_last_byte(dir, n) - reclen; while ((char *) de <= kaddr) { @@ -387,15 +390,11 @@ nilfs_find_entry(struct inode *dir, const struct qstr *qstr,
struct nilfs_dir_entry *nilfs_dotdot(struct inode *dir, struct page **p) { - struct page *page = nilfs_get_page(dir, 0); - struct nilfs_dir_entry *de = NULL; + struct nilfs_dir_entry *de = nilfs_get_page(dir, 0, p);
- if (!IS_ERR(page)) { - de = nilfs_next_entry( - (struct nilfs_dir_entry *)page_address(page)); - *p = page; - } - return de; + if (IS_ERR(de)) + return NULL; + return nilfs_next_entry(de); }
ino_t nilfs_inode_by_name(struct inode *dir, const struct qstr *qstr) @@ -459,12 +458,11 @@ int nilfs_add_link(struct dentry *dentry, struct inode *inode) for (n = 0; n <= npages; n++) { char *dir_end;
- page = nilfs_get_page(dir, n); - err = PTR_ERR(page); - if (IS_ERR(page)) + kaddr = nilfs_get_page(dir, n, &page); + err = PTR_ERR(kaddr); + if (IS_ERR(kaddr)) goto out; lock_page(page); - kaddr = page_address(page); dir_end = kaddr + nilfs_last_byte(dir, n); de = (struct nilfs_dir_entry *)kaddr; kaddr += PAGE_SIZE - reclen; @@ -627,11 +625,10 @@ int nilfs_empty_dir(struct inode *inode) char *kaddr; struct nilfs_dir_entry *de;
- page = nilfs_get_page(inode, i); - if (IS_ERR(page)) + kaddr = nilfs_get_page(inode, i, &page); + if (IS_ERR(kaddr)) continue;
- kaddr = page_address(page); de = (struct nilfs_dir_entry *)kaddr; kaddr += nilfs_last_byte(inode, i) - NILFS_DIR_REC_LEN(1);